Pneumatic flotation apparatus



M. KRAUT March 15, 1932.

PNEUMAT IC FLOTATION APPARATUS Filed'June l8,

INVENTOR.

ATTORNEY.

Patented Mar. 15, 1932 i UNITED ST MAX KRAUT, or sen rnnivciscqcmnronmn T PNEUMATIC FLOTATION nrri aArUs'i Application filed .l'une71 8,

1 l dium and consequent loss of time of operation of the apparatus; The costly maintenance has been occasioned by the frequent necessity of renewal of the porous medium which, due to the frequent cleaning, becomes worm, and

the fibers thereof brokenor damaged re-' sulting in holes which render the medium worthless. V The object of this invention is to provide a, pneumatic apparatus which is free from clogging, is self-cleaning, and which does not require the shutting down of' the entire apparatus for the renewal or replacement of one ofthe porous members.

The invention consists primarily in a member adapted for positioning inthe pulp body, and having flexible porous walls, the member being adapted for inflation and defiation'by a controlled air stream admittedthereinto to cause a weaving or movement of its walls, the air passing through the porous walls to aerate the pulp creating a froth and maintainthe surface of the member free from pore clogging-material. V j

With the above mentioned and other objects in view, the invention consists in the novel construction and combination of parts hereinafter described, illustrated in the accompanying drawings, and set forth in the claim hereto appended, it being understood that various changes in the form, proportion, size and minor details ofconstruction within the scope of the claim may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

To comprehend the invention, reference is directed to the accompanying drawings,

wherein r V Fig. 1 is a view in longitudinal broken section of the preferred embodiment of my invention illustrating in dotted lines one of the hose removed from the tank to admit of the renewalofits sack. Fig. 2 is a vertical'transverse sectional view onli'ne22 of Fig. 1. In the" drawings wherein; like characters i of reference designate corresponding parts, 1 indicates atank having a pulp inlet2, and a suitable discharge 3 The tank is divided longitudinallyby settling and circulation baf- 1928, serial" no. 28am. t

iles 54: and 5 which fall short ofcontactin'g with theta'nk bottom,'and with their adjacent edges terminating below the froth level to enable the froth withitsrecovered values to' pass under the lower edge of the baffle 5 and discharge from theoverfiow 6. Suitable separating partitions 7 are positioned transversely of the tank at intervals and terminate short of the'bottom thereof, 1 i

' Disposed above 'the tank and extending longitudinally. of the'centerthereof is an air conduit or pipe'8 mounted on brackets 9 and supplied with F air under pressure from any suitable sources'uch as a pump or blower. Couplings 10 communicate with thefinterior' of the air "pipe 8 at intervals "throughout its length, and 'eaclr'Iiiounts'a cut on valve 12 and an intermittently operated valvell. "The valve'12"controls the admission of air from the pipe 8 to valve 11 and the latter valve c0111 trols the intermittentdischarging of theair 7 from the. coupling. Suspended from each coupling is a section of flexible hose 13 depending into thetankto a'point near-the bottom thereof, and detachably positioned-over the lower end of each hose is a fabric bag 14 preferably of heavy canvas. The bags when not subjected to air pressure assume a col lapsed position, this being caused by the pressure of the pulp on the exterior surface there .o

The valves 11 areillustrated as connected together by a common operating rod 15., The

rod 15 is intermittently reciprocated by an Y .1

operating mechanism 16 of any suitable type;

With the parts positioned as in the drawings, and the valves 12 adjusted to open position, the'intermittent operation ofrod 15 by mechanismclti will intermittently open and close valves 11 causing air to passthrough the hose '13 inflating. the respective bags 14:, an

passing therefrom through the porous bag walls removing from the exterior surface thereof any particles of material having a tendency to adhere thereto and clog the same. The flow of air into the bags is cut off when valves 12 are closed and the weight of'the pulp causes a deflation or collapsing of the bags; thus the inflation and deflation of the bags causes a weaving or flexing of the bag forming material which agitates any mate'- rial adhering to the surfacerendering itcomr paratively easy of dislodgment by the air streams passing outwardly through the-bag walls. The air passing through the porous bags dries the pulp and creates a froth which carries the recovered values, and which overflows at 6'. l

To renew or replace any particular bag it is only necessary to close -it s:a-ssociatedvalve 12, bend its mounting hose to lift the bag free from the pulp at which time the bag can be renewed and the bag and hose thereafter dropped back into the tank with the bag suspendedon the end of the hose. This change is accomplished without interrupting the operation of any portion of the apparatus exceptthat hose mounting the bag requiring the renewal.

I claim z- In a pneumatic flotation apparatus having a tank for pulp, means to aerate the pulp comprising an air duct overlying the tank, a plurality of independent flexible conduit members depending from and communicating with the air duct and'having one end eX- tending'into the tank to a position adjacent the bottom of. the tank, an independent singlechambered bellows member provided with a porous flexible wall mounted at the end of and supported'bythe independent flexible conduit members in communication with said conduit, and meansto intermittently introduce air into said: bellows members from said air duct. 7

In testimony whereof I have signedmy name to this specification.

MAX vKRAUT. 

